Ah, the party conferences! Three weeks of airless auditoriums and sterile hotels, long speeches and short motions, gossip, intrigue and cliche.

Please repeat after me: it is the most important speech of his life; he was speaking to the country not the party; the defeat on the floor is a devastating blow to the leadership. And so, and so on.

Party conferences are part of the rhythm of political life, the annual gathering of political party members known variously and archaically as the party faithful, rank and file and grassroots.

It is a chance for them to chastise their leaders and be inspired by them, to mix and mingle over cheap wine and stale sandwiches, but above all, to remind themselves of why they are what they are and do what they do, gaining succour from sharing time with like-minded folk who do not think it odd to go out canvassing on a wet Thursday night or spend hours licking envelopes in the often vain hope they may be making a difference.

And there is always the excitement of the leader's speech, the danger of the fringe, and the occasional thrill of the votes.

But this year the conference season will be different, and not just because for the first time in many years no party is heading to the seaside for their annual sojourn.

Liberal Democrats

The Liberal Democrats are in government and therefore matter. For years only the dedicated, the devout and the dutiful went to Lib Dem conference.

Now it has ballooned in size with more delegates, more media, more lobbyists coming to Liverpool than before. But will some of them have been lured there under false pretences?

The Lib Dems can pass as many motions as they like but Nick Clegg's aide, Norman Lamb, has made it very clear that they will not change a jot of government policy.

The holy writ is the coalition agreement, not the latest missive from the Lib Dems' federal executive.

That said, this conference will matter because it will allow us to judge for the first time since the election just how much slack the party is willing to give Mr Clegg as he leads them into a very dark place where there are few votes to be had.

Some Lib Dems fear Mr Clegg is taking a risk by leaving his conference early to head for the United Nations in New York.

But before he goes, do not expect the Deputy Prime Minister to trim on spending cuts.

His big fear is not unpopularity with voters and his party. His fear is that he goes through all this pain and is unrewarded when - or if - the coalition leads the country back into the promised land of economic recovery. He is determined that the gain, as well as the pain, is shared.

Labour

Party conferences after electoral defeat tend to be miserable affairs. There is recrimination, hindsight, the broken dreams of what might have been.

So what better way to cheer everyone up than to elect a new leader? Fresh start, new broom, onwards and upwards.

Thus in Manchester Labour will announce on Saturday which Miliband brother it has chosen as Gordon Brown's replacement and begin its conference the following day.

And there is no reason why thereafter they cannot have a good week. Why?

Because it better to have a leader than not to have one.

Because for the first time in a long time the party will be able to face out rather than in, addressing the country and not themselves.

Because the new leader will enjoy at least some sort of a political honeymoon.

And because they will finally start to do what oppositions are supposed to do and oppose.

But if the new leader fails to impress, if a defeated candidate sulks, if the Shadow Cabinet election campaigns get nasty, then the party risks missing an opportunity.

The key question facing the new leadership is what they say about the spending cuts.

This is the defining issue of the autumn, if not the next year.

How will the new leader position the party so that they can have a credible position on cutting the deficit while opposing some of the government's cuts?

Conservatives

For the Conservatives, their conference is an hors d'oeuvre before the main course of the spending review.

It is not the speeches made in Birmingham that matter, but the speech that George Osborne makes in the Commons on 20 October.

The purpose of the conference will instead be to prepare the way for the cuts, using the week to make the case once again for spending less, fast.

There is a sense at Westminster that the government has let the argument drift, getting sucked into individual fights with the police or the unions, allowing the wider case for cutting the deficit to fall by the wayside.

So expect David Cameron once again to claim that his spending cuts are unavoidable and that swinging the axe more slowly and less deeply would put the recovery at risk.

But the prime minister is also keen to try to avoid the government being defined by cuts alone.

So expect too an attempt by the Tories to show a little more ankle of their planned reforms - on education, on health, on transport. But they will be nibbles, not a square meal, for which we must wait some weeks.

The other interesting question is the mood of the party members.

Many spend their lives fighting Lib Dems and are uneasy at the coalition.

Some believe Mr Cameron squandered a good poll lead and lost the election.

BBC links

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